I have been to Salou loads of times and i have once seen 2 spanish lads fighting, no big fisticuffs just a bit of shoving, they were drunk i think.
I have never encountered big gangs/groups, even if there was the police are around the resort ALOT so would move them on.
As for pickpockets my hubby (who we will call the idiot on this occasion
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) got his wallet taken from his back pocket while he got on a bus, there was only a few euros in it but its not the point. Had he hidden it or put it in my bag it would have been safe
It certainly never stopped us going back umpteen times after the incident.
Dont worry too much, you could get worse done to you in this country.
Use common sense as you would at home and use the safes in the hotels so that your money and things are safe.But most of all
Have fun xxxxxxx
Where are you staying?